Re: [Discuss-gnuradio] ICE1712 and ALSA sink

[Marcus D. Leech]

On 07/17/2011 06:19 PM, Alex DEKKER wrote:
> Built GNUradio from git on Debian Testing AMD64 this afternoon, and 
> intending to use it with a Funcube Dongle and gr-fcd. I am having some 
> difficulty with the ALSA sink and an ICE1712 [M-Audio 2496] sound 
> card. I created a very simple flow graph with a sine wave Signal 
> Source straight in to an Audio Sink. When I try to execute it, I get:
>
> Traceback (most recent call last):
>   File "/home/alex/downloads/radio/gr-fcd/apps/top_block.py", line 
> 118, in <module>
>     tb.Run(True)
>   File 
> "/usr/local/lib/python2.6/dist-packages/grc_gnuradio/wxgui/top_block_gui.py", 
> line 72, in Run
>     if start: self.start()
>   File 
> "/usr/local/lib/python2.6/dist-packages/gnuradio/gr/top_block.py", 
> line 97, in start
>     self._tb.start()
>   File 
> "/usr/local/lib/python2.6/dist-packages/gnuradio/gr/gnuradio_core_runtime.py", 
> line 1480, in start
>     return _gnuradio_core_runtime.gr_top_block_sptr_start(self)
> RuntimeError: audio_alsa_sink(3): insufficient connected input ports 
> (10 needed, 1 connected)
>
> > > > Done
>
> I have connected an old USB sound card, which becomes hw:2,0 and 
> pointed it at that, and it works fine. So there seems to be some kind 
> of incompatibility between gnuradio and this sound card. Where is the 
> best place to start looking into what the issue might be?
>
> alexd
So, the audio_alsa_sink.cc module queries the ALSA subsystem for the 
min_chans that it offers, and configures the I/O configuration for
  Gnu Radio accordingly.  Near as I can tell, your reported error 
indicates that the ALSA driver is reporting that the *minimum* number of
  supported channels is 10, which is a bit odd.  No, it's very odd.  I 
can imagine a card only supporting stereo input, and not mono.  But
  a minimum of *10" channels?  That sounds like a bug in an ALSA driver 
to me.




--
Marcus Leech
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org